1. Field of the Invention
The present invention relates to a combustion controller for a combustible gas of a pressurized water reactor nuclear power plant, and more particularly, to a combustion controller for a combustible gas installed in a rear end of a filtered vent system outside a containment vessel or an external chimney, configured to convert a combustible gas such as hydrogen, carbon monoxide, or the like, into steam, carbon dioxide, or the like, and simultaneously, operated by itself with no external power supply.
2. Discussion of Related Art
While a filtered vent system of a containment vessel installed at a nuclear power plant performs a function of discharging hydrogen, carbon monoxide and a non-condensable gas to the atmosphere, when hydrogen and a combustible gas are rapidly discharged to the atmosphere, combustion of the hydrogen occurs. In particular, when air is introduced from the outside, combusted flame may cause a backfire in a direction of filtered vent equipment. Accordingly, as the flame is generated, an exhaust tower or an exhaust chimney may be damaged, and of course, when the backfire occurs, the equipment may be seriously damaged according to circumstances. In particularly, when carbon monoxide is incompletely combusted to be directly discharged to the atmosphere, the carbon monoxide may be harmful to human bodies.
Meanwhile, a passive apparatus for removing hydrogen is installed in the containment vessel. The passive apparatus is a passive autocatalytic recombiner PAR system. According to a scale of the containment vessel of the nuclear power plant, about 20 to 40 passive apparatuses are installed to remove hydrogen from the containment vessel through hydrogen catalyst combustion.
The above-mentioned conventional PAR is a passive PAR disclosed in Korean Utility Model Publication No. 20-0464123, and includes a cover body having an inlet port formed at a lower end thereof and through which air including hydrogen gas is introduced, discharge ports formed at three surfaces of an upper end thereof and through which the introduced air is discharged, and a guide plate inclined from the three surfaces toward the remaining surface to guide the air flow to the discharge ports; a honeycomb type catalyst body mounted on a lower end of the cover body to react with the introduced hydrogen gas to remove hydrogen; and a catalyst body housing assembly, on which the catalyst body sits, configured to detachably mount the catalyst body on the lower end of the cover body, wherein a roof plate installed on the three surfaces, in which the discharge ports are formed, is provided on an upper end of the cover body to prevent liquid dropped from above from being introduced into the cover body through the discharge ports.
However, even when an automatic catalyst coupler is installed in the containment vessel, a combustible gas such as hydrogen, carbon monoxide, and so on, in the containment vessel is discharged to the atmosphere through the filtered vent equipment while being incompletely oxidized when the combustible gas is exhausted to the outside of the containment vessel through the filtered vent equipment. Accordingly, even when the passive automatic catalyst recombiner disclosed in the related art is installed in the containment vessel, additional equipment is needed to remove a combustible gas such as hydrogen or carbon monoxide, which is unavoidably discharged to the outside. However, the PAR disclosed in Korean Utility Model Publication No. 20-0464123 is a structure that cannot be installed at the rear end of the filtered vent equipment outside the containment vessel or the external chimney.